The tanpura (or tambura, tanpuri) is a long-necked plucked string instrument found in various forms in Indian music; it does not play melody but rather supports and sustains the melody of another instrument or singer by providing a continuous harmonic bourdon or drone. A tanpura is not played in rhythm with the soloist or percussionist: as the precise timing of plucking a cycle of four strings in a continuous loop is a determinant factor in the resultant sound, it is played unchangingly during the complete performance. The repeated cycle of plucking all strings creates the sonic canvas on which the melody of the raga is drawn. The combined sound of all strings, each string a fundamental tone with its own spectrum of overtones, is a rich and vibrant, dynamic-yet-static tone-conglomerate, due to interactive harmonic resonances that will support and blend with the external tones sung or played by the soloist.